API Reference

Ie_with_LET(E₀, Q, E, dE, μ_center, BeamWeight, Beams; low_energy_tail=true)

Return an electron spectra following a Maxwellian distribution with a low energy tail (LET)

This function is a corrected implementation of Meier/Strickland/Hecht/Christensen JGR 1989 (pages 13541-13552)

Arguments

• E₀: characteristic energy (eV)
• Q: total energy flux into the ionosphere (eV/m²/s)
• E: energy grid (eV). Vector [nE]
• dE: energy bin sizes(eV). Vector [nE]
• μ_center: electron beams average pitch angle cosine. Vector [n_beams]
• BeamWeight: weights of the different beams. Vector [n_beams]
• Beams: indices of the electron beams with a precipitating flux
• low_energy_tail=true: control the presence of a low energy tail

Returns:

• Ie_top: differential electron energy flux (#e⁻/m²/s). Matrix [n_beams, 1, nE]

Important notes

This is a corrected version of the equations present in Meier et al. 1989 to match the results presented in Fig. 4 of their paper.
Changes were made to the factor b:

• no inverse

Examples:

Calling the function with flux only in the two first beams (0 to 20°) and an "isotropic" pitch-angle distribution.

julia> E, dE = make_energy_grid(100e3);

julia> θ_lims = 180:-10:0;

julia> μ_center = mu_avg(θ_lims);

julia> BeamWeight = beam_weight(180:-10:0);

julia> Ie = AURORA.Ie_with_LET(1e3, 1e10, E, dE, μ_center, BeamWeight, 1:2);

Calling the function with flux only in the three first beams (0 to 30°) and a custom pitch-angle distribution (1/2 of the total flux in the first beam, 1/4 in the second beam and 1/4 in the third beam).

julia> E, dE = make_energy_grid(100e3);

julia> θ_lims = 180:-10:0;

julia> μ_center = mu_avg(θ_lims);

julia> BeamWeight = [2, 1, 1];

julia> Ie = Ie_with_LET(1e3, 1e10, E, dE, μ_center, BeamWeight, 1:3);